Nonfreezing oil system



Oct. 9, H WQQD NQNFREEZING OIL SYSTEM Filed April 2, 1948 INVENTOR.e/flWood,

be seriously damaged within a short time.

Patented Oct. 9, 1 951 NGNFREEZIN OIL SYSTEM Roger H. Wood, Tomah, Wis.

Application April 2, 1948', Serial No. 18,588

1 Claim. (Cl. 184-6) The present invention relates to an improvednon-freezing oil system which has particular application to thelubricating-systems of internal combustion engines.

In all internal combustion engines there is a tendency for water togradually accumulate within the crank case during the interval betweenoil changes, "and this accumulation can 'become quite substantial undercertain driving conditions, particularly with lealry piston rings, longintervals between'oil changes, etc.- In calities which are subject torather cold winters the freezing of this accumulation of water withinthe crank case can create pronounced lubrication difiiculties. Theaccumulation of water remains below the oil, and ifthisaccumulation isof suiiicient quantity to extend up to or slightly above the lower endof the oil line, the freezing of the water at this point can totallyblock the oil line. This fact is rendered particularly hazardous,because the water collects in a place where the operator of the vehiclecannot observe it and therefore cannot know what the current water levelis, but can only know whatthe water level is after the oil system hasbecome frozen and the motor is being operated without oil. Moreover, ifhe should not be watching his oil gauge closely he would not be aware ofthe condition even then. If the engine is operated with the oil linethus blocked bytruck drivers, filling station operators, etc. is to'direct the flame of a blow torch against the under side oi the oil panof the car, truck or'tractor. This is a diflicult, hazardous operationwhich must be repeated every morning or after every interval when theengine stands idle for sometime in cold weather. 7

My invention avoids these diflficulties by provviding an improved safetyby-pass in association with the conventional suction inlet pipe whichsupplies oil from the sump or lower levelof the crank case to the oilpump. "This safety (by-pass is normallyclosed or does not normally passoil from the crank case sump'to'the oil Freezing of the inlet end of thesafety by-pass :is prevented by a unique construction and warrangementwherein the safety by-pass draws from a non-freezing level which isdisposed between the lower suction level of the suction inlet pipe andthe top liquid level of the oil standing at the normal or average oillevel in the crank case. This nonfreezing level is main tainednon-freezing by virtue of a sufiicient differential above the lowersuction level and by virtue of the fact that the accumulation of waterwithin the crank case is prevented from rising appreciably above thislower suction level because of the inherent vaporization of the water indifferent parts of the engine and of the crank case when sucked up intothe lubricating system. This will be explained more fully in thefollowingdetailed description of several preferred embodiments of theinvention. In the accompanying'drawings illustrating such embodiments:

Figure 1 is a fragmentary, sectional View through the crank case andlower portion of an internai'combustion engine illustrating theapplication of my invention thereto.

Figure 2- is .a fragmentary, vertical, sectional .view through oneembodiment of the invention.

Figure 3 is a side view of this type of embodiment, also illustrating aninverted cup attached to the suction inlet pipe for the oil pump andshowing the oil drain plug with an attached through still anotherembodiment.

Figure 1 is illustrative of any conventional design of internal"combustion engine comprising a crankshaft l6 mounted in main bearingsll and having operative connection through connecting rods i2 withpistons reciprocating in the engine cylinders. The conventional crankcase is indicated at the lower part of which defines an ,oil-Sump l6containing the lubricating oil H.

a The-crank case is usually provided with a remov- "pump. However, ifthe normal flow through the V suction inlet pipe is blocked by ice, thenthe safety by-pass automatically opens'or automatiically permits oilflow therethrough inashunt .around the frozen end of the suction inletline.

ableoil pan, as is well known.

'iiie lubricating system of engine is sup- In the typical constructheoil sump. Directly below this inverted cup 2|, the crank case or pan isprovided with a drain opening 23 which is normally closed by theremovable plug 24, the latter having threaded mounting in the drainopening. A straining screen 26 of cylindrical form extends upwardly fromthe drain plug 24 into the inverted cup 2| to a point near to the underside of the closed upper end of the cup. Thus, the oil passing to thepump through suction inlet pipe I9 is normally strained through thescreen 26, but if the screen should become clogged with sludge, then theoil is sucked up over the top of the screen and then into the inletpipe.

Referring first to the embodiments illustrated in Figures 2 and 3, thesuction inlet pipe I9 extends downwardly within the inverted cu 2| andis formed with a flared lower end 28 defining the suction opening I9.This suction opening I9 is located at a relatively low level in thecrank case and lower than the level of the rim of the inverted cup. Thesafety by-pass of my invention is shown in the form of a syphon tube 3|in the embodiments illustrated in Figures 2 and 3. This syphon tube hasits lower intake opening 3| disposed at a substantially higher levelthan the intake opening I9 of the main suction inlet pipe I9. From thishigher intake opening 3| the tube 3| extends upwardly and then curvesdownwardly to define an inverted U or syphon bend 32. The downwardlyextending leg of the syphon bend opens into the suction inlet pipe I9through the lateral port 33.

If desired, the syphon bend may be curved over a sloping portion of theinlet pipe I9, as shown in Figure 2, and this syphon bend is preferablylocated above the cup (Figure 3) so that it will have a substantialheight above the inlet opening 3|. An air pocket 34 will form in thebend or bulge 32 for controlling the syphon flow through the safetyby-pass 3 I.

Referring now to the operation of the embodiments as shown in Figures 2and 3, attention is first directed to the four liquid levels designatedAA, BB, C-C and D-D. Level A-A diagrammatically represents the surfacelevel of the body of oil I I when the oil stands at a normal or averagelevel corresponding to a normal or average sunply of oil in the crankcase. The intermediate level BB indicates that level from which thesyphon tube 3| will draw when the safety by-pass is in operation byreason of an ice blocked condition of the suction inlet pipe I9. Thelevel CC aproximately indicates a water level substantially coincidentwith or slightly above the level of the intake opening I9, which waterlevel would be adequate to freeze the inlet opening I9 shut. Level D-Dis approximately shown as being slightly below suction opening I9, andindicates approximately a typical water level in the crank case duringthe time that the engine is running. A substantial accumulation of watercan collect quite ripidly in the crank case of an internal combustionengine, largely from the products of combustion leaking past the pistonrings and condensing in the crank case. Let us assume that thisaccumulation of water has reached approximately the level C-Csubstantially coincident with or slightly above the suction inletopening I9. When the engine is started the' suction inlet pipe I9 firstdraws water to the lubricating system, this continuing until the waterengine is approximately indicated at DD. Because the suction openingcannot draw water below this level DD, it follows that the quantity ofwater represented by the level DD will remain substantially permanentlyin the crank case until the crank case is drained in the operation ofchanging oil. If two much water collects in the crank case, it is suckedup and sent through the motor, with the result that much of it isvaporized and leaves the crank case through the breather. When theengine has stopped running a residual accumulation of water in diiferentparts of the engine tends to flow back to the bottom of the crank case.This running accumulation of water in the engine includes waterentrained in the oil, and water vapor in the crank casewhich condenseswhen the engine stops, and also other droplets of water adhering to thesides of the crank case, etc. With the return of this runningaccumulation of water to the bottom of the crank case, the water levelis quite likely to be brought up to the suction inlet immersion levelindicated approximately at CC Then, if a protracted spe l of extremelycold Weather occurs, this water freezes across the inlet opening I9 andtotally blocks oil flow through this opening when the engine is againstarted. As a result of this blocked condition at the opening I9, arelatively large suction is established in the suction inlet pipe I9,with the result that oil is drawn up through the by-pass inlet 3| andover the syphon bend 32 and through port 33 into the suction inlet pipe,as indicated by the directional arrows. The accumulation of water doesnot reach up to the intermediate level BB and hence there is no iceblocking the bypass inlet 3|. Thus, oil is supplied immediately to themotor through this safety by-pass, and such supply continues during therunning of the motor until the crank case has become sufficiently warmto melt the ice blocking the main inlet opening I 9, whereupon the oilflow through the by-pass 3| is interrupted and the oil flow through theinlet opening I9 is resumed. From the above-described operation, it willbe seen that the main suction inlet I9 exerts a controlling influenceupon the water level in the bottom of the crank case, tending to confinethis water level substantially between the two levels indicated at C-Cand DD, so that the water level is never allowed to reach up to thepoint BB where it might freeze shut the by-pass inlet 3|. In this sameregard, it is also important that the by-pass inlet 3| beentirely'independent of the main inlet I9, so that it does not have todraw its supply of oil through the same inlet opening or at the sameinlet level that constitutes the normal or main supply. When the ice inthe inlet opening I9 thaws out and flow through this opening resumes,the by-pass flow through tube 3| automatically stops because the airpocket 34 in the syphon bulge 32 prevents the oil from syphoning overthe hump. It will be seen that the distance which the oil has to beraised above the normal surface level AA, in order to lift it over thehump at 32, is substantially greater than in the case of oil lifteddirectly from this level AA to the level of the port 33. Hence,

' no fiow occurs through the by-pass when normal level drops to a ointjust enough below the inlet 7 flow can occur through the main suctionopening I 9'.

Referring now to the modified embodiment of the invention shown inFigures 4 and 5, in this construction the safety by-pass comprises asmall check valve housing 35 which is secured to or formed integral withthe side wall of the suction inlet pipe 19 at a point adjacent the upperend of the entrance funnel 28. The open lower end 35 of this housing 35constitutes the by-pass inlet opening adapted to draw oil from theintermediate oil level BB. A necked or tapered bushing 36 extendsupwardly within the housing 35 to form a valve seat 6'! for the ballcheck valve 38. The chamber area above the valve seat 37 opens laterallyinto the suction inlet pipe i9 through registering openings 36 and 40 inthe housing and in the pipe. Under normal operating conditions the checkvalve 38 seats on the valve port 31, since there is an insufiicientsuction differential acting upon the ball to lift it from its seat.However, as soon as the main suction opening l9 has become closed orsufficiently constricted by ice to create a substantial suction withinthe suction inlet pipe 19, the check valve 38 thereupon lifts off itsseat and permits a bypass flow of oil through Toy-pass opening 35 andthrough registering ports 39 and es into the pipe l9. The by-p-assaction of this embodiment will be understood from the detaileddescription of the preceding embodiment.

In Figures 4 and 5 I have shown a supplementary feature which may beemployed, if desired. This consists of a narrow notch 42 cut through thebottom portion of the suction inlet pipe or funnel at one side thereofadjacent to the bypass inlet. This slot is of benefit because it permitssome oil to flow through the upper part of the slot when the lower partof the slot is closed or constricted by ice. The slot is also beneficialin that it enables oil to flow through the regular suction inlet, morepromptly after the oil has started to warm up than if such slot is notincluded. Such arrangement of slot may also be provided in theembodiments shown in Figures 2 and 3, preferably with the slot at oneside adjacent to the by-pass inlet opening 3|.

In Figure 6 I have illustrated still another embodiment of my inventionwherein the safety bypass flow occurs through a spring-closedsuctionresponsive valve, preferably mounted in the funnel 28 or otheradjacent portion of the suction inlet pipe I9. This valve designated 45opens inwardly from a valve port 46 formed in the side of the funnel 28.A stem 41 extends outwardly from the valve and passes through a spider48 provided in the valve opening 46 and through an angle-shaped guidebracket 49. A compression spring 51 on the valve stem acts between thespider 45 in its closed position. The lower part of this valve and itsport are disposed at a nonfreezing intermediate level BB above thelevels susceptible to freezing. Hence, in the event that the suctioninlet opening l9 becomes closed or substantially constricted by ice,this safety bypass valve 45 remains free to open to permit oil to flowto the pump until the motor has become sufiiciently warm to thaw out theice in the opening 19', whereupon normal flow is resumed through thisopening and the valve 45 closes. The operation of this embodiment willbe clearly understood from the operation of the embodiments shown inFigures 2 and 3.

With regard to situations where the straining screen at the inlet end ofthe oil pipe might become plugged up by sludge alone, or by ice alone,or by both, the invention can be adapted to those situations indifferent ways. For example, the top of the straining screen 26 canterminate slightly below the under side of the closed upper end of thecup 2!, so that if the screen should become plugged up by sludge the oilcan still flow over the top of the screen and reach the suction opening:9. Another way is to have the syphon tube 3| of Figures 2 and 3 extenddown on the outside of the screen 26 and of the cup 2|, in which casethe lower rim of the cup 2! must extend down to a level equal to that ofthe oil pipe suction inlet and lower than that of the syphon tube 3!. Inthis latter arrangement with the syphon tube 3! disposed on the outerside of the cup 2|, the upper end of said syphon tube could also bearranged to empty into the upper portion of the cup, in which case thelower rim of the cup would have to extend down to a lower level than theregular oil pipe I9 and also to a lower level than the syphon tube 3|.In this arrangement the lower end of the regular oil pipe I9 preferablyhas one or more relatively deep notches 42 in its lower end and alsopreferably does not extend down to a level much lower than half way fromthe level of the rim of the cup to the closed upper end of same where itis attached to the regular oil pipe.

While I have illustrated and described what I regard to be the preferredembodiments of my invention, nevertheless it will be understood thatsuch are merely exemplary and that numerous modifications andrearrangements may be made therein without departing from the essence ofthe invention.

I claim:

In an internal combustion engine comprising a crank case adapted tocontain oil and an oil pump adapted to pump oil therefrom through thelubricating system of the engine, the combination therewith of a suctioninlet for the oil pump having a low-level suction opening normallydrawing oil or water from a relatively low level in said crank case, anda syphon tube safety by-pass having an inlet opening disposed above saidlow-level suction opening for drawing oil from an intermediate levelwhen said low-level opening is blocked by ice, the discharge end of saidsyphon tube discharging into said suction inlet pipe.

ROGER I-I. WOOD.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,399,943 Dunham Dec. 13, 19211,568,796 Breer Jan. 5, 1926 1,648,910 Cooper Sept. 18, 1928 1,874,976Hans Aug. 30, 1932 2,285,997 Mino June 9, 1942 2,372,286 Mieras Mar. 27,1945

